Misc improvements and added tests

• Moved logger in preparation for logging in Scheduler.
• Removed some old Qt5 stuff I found.
• Greatly improved performance of ListScheduler, especially for large schedules.
• Added a bunch of new tests.

b_asic/gui_utils/mpl_window.py

 """MPLWindow is a dialog that provides an Axes for plotting in."""
 
-from matplotlib.backends.backend_qt5agg import FigureCanvasQTAgg as FigureCanvas
-from matplotlib.backends.backend_qt5agg import NavigationToolbar2QT as NavigationToolbar
+from matplotlib.backends.backend_qtagg import FigureCanvasQTAgg as FigureCanvas
+from matplotlib.backends.backend_qtagg import NavigationToolbar2QT as NavigationToolbar
 from matplotlib.figure import Figure
 from qtpy.QtCore import Qt
 from qtpy.QtWidgets import QDialog, QVBoxLayout